Arm supported universal portable power tool



April 18, 1950 c. RITTENHOUSE 2,504,839 ARM SUPPORTED UNIVERSAL PORTABLE POWER TOOL Filed May 23, 1946 2 Sheets-Sheet 1 IN V EN TOR.

2/: CHARLES RlTTENHOUSE. BY

2.9 TM *TM ATTORNEYS April 18, 1950 c. RITTENHOUSE ARM SUPPORTED UNIVERSAL PORTABLE POWER TOOL 2 Sheets-Sheet 2 Filed May 23, 1946 56 INVENTOR' CHARLES RITTENHOUSE.

ATTORNEYS a yp s of machinin 'pei fat portable pdwelr drive UNITED STATES PATENT QEFICE.

sumsssnumvmsn roe-mam BQWER TOOL Gharres Rittenhnuse, Cincinnati, Ohio Application, Ma 23, 1946, SerialNb. 671,795

- I. This invention pertiai tof pcrtahle QOMZQI'" driven to nd is par icularly lie 'at i a n vessel portabl electr tool a; lar e va ety etch such as dr"1ing, fi1idllflghmT diIlg bum gbrushing c isawing One of he, QDjGQtSQQf h s, ih e l fiin" is vi p rtable p w clr ven 0.01 which may e 1 carried: and manipu ated by the operatoz' with gr at eesea d ccumy Qfj control- 'epfied to perio a; series. of, different vsen; amther'objecm l nventiicnist o-pr e videaportable electric. toil whi h m y e -ried cnthefcrearm'and manipulated by'the hand fin, perfectly balanced, easily ,cqnti ollable manmate-1161162111 a. wide variety of dififere'nt; types; of vtoperattil' ns.

It is 3180 the object,

:and the, like toe s, soles V gri d ng e i Another chj'ectj is ts provide; a power" difiveii tool carried, on theiqfehrghf of the cperatqi m such a We ly that it, mar be rotated in" a; vertical plane While" maintaining eififcient manual" controf at allltin'ies of the l wer tcol' tci facifitet'ef the performance of such operations as sandii iig afhd theme. 7

And a furthefobjet of this inventionis to rcvide e po teblee l M carried thin niplllj ated' by the" a m'ofr the o1 carrying head'- with a 15111 Further Teatures'a'nd advahteges or-this-inveh adap d p fo m 1; types cf operations 1; universally adapt :a h1e. to perfji mm ai'la gge'valriety'of workwitha? siege pgwer dr ven tfocL, c

{1 s b reg-any sgsptthe toi to IS 1 atlarge variety o'f'di-fierent types Claims. (Cl. 143-43) tion w ll; e r i m a eta led d s ri tiqn; 0t edrawings. in which: t

Fi ure 1 is a. view sh in t pq b s w tool being operated tO' perform a, dfi'lling 'peretion one work piece. 7

F 'suite 2 is' an enla ged fr m n ar j i itndi rial section on the; line 2 -2 pi Eigu l e 3; through thetcol spindle hcusing'Qfj the pewer t l.

Figure 3 isa transverse section on the line 3+3 of Figure 2;;

Figure 4, is a treg'mentery tija ns'verlse seqfltidn cnthe 1ine-4'-% ofliigui e 2,,

Figure 5. is a fra m nt, ci the 1 ne '5"5; f Fi ure 2i Figur 6 shows the tool .11 use performing a i op rat e;

Figure Tis a. fragmentary side view' of the tool; arra ged o sewin nd ed by e ne in Figure 8., H

Figure 8 is a; fragmentary View, partly in sec tion'cri the line8"-8 ofFig ure '7'.

'ry transverse secticn Figure 9 i a fragmentary View indicated by the l ,9Qf Fi u e The portable power driven tool incorporating" the torque'tnbe" 12 bye, suitablethreaded connection l3, The-tool spindle housing or member I rnfey'be similai ly cohnectedtc the torque tube l2 by a suitable threaded. connection M; The driving meter H has an elongated drive shaft l5 extendingthrough the torque tube l2 '4nd 0611; mated by avsuitablekeyed driving connection I16 with the tdql spindle IT, The spindle is 10111"- nale'd on antifi iction bearings &5" and I9 iplthe tool spindle hqgsing' I 3 and iSfprQVidQd with a threaded connection 2fi'to which ma be attached vefibus tdol holder mandrelssuch as themaind el 2! which is adapted to ca'rr'y various tool holdei chuclgssuchas the drill chuck 22; Figure 2.

Refined oh the spindle I1 is e; spiralgeer 23" which is in driving engagement with a; mating spiral gear 24 formedona tccl'spind1e25. The

spindle is jionrnaled on suitable antifr-iction bear ing's ZGiahd 21in the tool spindle housing I'pei -Q pendiculai' to the spindle I! and-projectingo t wardly each side of the housing H; Qn' each end of the shaft 275 there is prdvidedt-he same threaded connections 20, as in the case of the spindle ll, tc whic'h may be connected va rieus mandrels, esthe mandrel am for; mounting asanding-disc 28 and ama -ndrel H'b formbunting a grinding wheel 29. Thus, from the same tool spindle housing N there are provided three threaded connections for application of various types of cutting tools. Any variety of different types of tools may be similarly applied to the various spindle outlets 20, as for example the mandrel for mounting the circular saw 3|, as best seen in Figures 6, '7, and 8.

A novel arrangement is provided for carrying and manipulating the tool with great ease and nicety of control comprising an arm hook 32 having a suitable curved arm pad 32a which is placed over the forearm A adjacent the elbow, as best seen in Figures 1 and 6. This arm hook 32 has a hinged connection at 33 with an adjustable clamp 34 which may be clamped to the torque tube 42 by means of a suitable thumb screw 35, Figures 4 and 5. The clamp 34 is adjusted longitudinally on the torque tube l2 and clamped by the thumb screw 35 so that the weight of the motor I!) substantially balances the weight of the tool spindle housing in order that the tool spindle housing may be maneuvered with great ease and nicety of control by the operator.

In order to facilitate the manipulation and direction of the tool spindl housing H and its respective tools, such as the drill 22a to proper position on a work piece W, there is provided a vertically disposed control handle 38 preferably positioned directly above the tool spindle housing The handle 38 is fixed by a suitable threaded connection 39 to a rocking lever arm 40 having a hub portion 4| journaled at 42 on the torque tube l2 and confined axially on this torque tube by abutting against the surface 43 of the housing H and the surface 44 of a collar 45 attached to the torque tube 2 by a pin 46. Thus, the handle 38 may be swung around the torque tube axis 31 from a position 38a, Figure 3, to a position 38b. The handle may be locked in either of these positions 38a or 38b by means of the knurled thumb screw 41, carried in the hub portion 4| of the handle, which may be engaged in detents 41a or 4112, respectively. An electrical control switch 48, actuated by the finger grip lever 49, may be operated by the operators index finger to control the stopping and starting of the drive motor Ill.

.When it is desirable to utilize the tool, for example, to perform drilling operations as in Figure 1, the control handle 38 is positioned with the knurled screw 41 in the detent 41a, as shown in Figures 2 and 3. When, however, it is desired to do sanding operations by placing a sanding disc on the spindle 25 in place of the grinding wheel 29 and removing the sanding disc 28 and mandrel 2|a from the other end of the spindle 25, it is preferable to rotate the handle 38 to the position 38b, looking it in this position by engagement of the knurled screw 31 with the detent. 4727. This places the control handle 38 in a position perpendicular to the sanding disc for the proper application of the disc to the work surface to be sanded. In other words, during sanding operations or when it is desired to use some other tool in the spindle 25 in which force is best applied parallel to the axis of the spindle 25, the control lever 38 may be readily positioned at 38b so that it will be substantially parallel with the tool spindle 25.

It should be noted that the hinged connection 33 for the arm hook lies substantially on the center of gravity 35 of rotary balance of the.

relative to the axis 3'! of the torque tube. As a result, when rotating the control handle 38 t0 the position 38b, the arm hook 32 likewise swings on the hinge 33 to the position shown in Figure 5. The hinge 33, being substantially on the center of gravity 36, will maintain the tool in proper balanced condition around the axis 31 of the torque tube so that there will be no tendency for the tool to swing around the arm of the operator. Thus, a fully balanced condition is maintained in the tool when using any of the tool spindles while at the same time allowing the proper positioning of the control handle 38 and the arm hook 32 for effecting different types of operations with various types of tools mounted on the various tool spindles. It should be further noted that by this arrangement of carrying the weight of the tool on the forearm A in balanced condition by means of the arm hook 32 and by providing the control handle 38 for manipulating and controlling the position of the tool being applied to the work W, the operator's other hand H is free to manipulate and hold the work W and otherwise steady the operation, a condition not obtainable with more conventional types of portable power tools.

In Figure 6 the'power tool is shown arranged for sawing with a saw 3| mounted on the mandrel 30 on the spindle 25. A saw plate 5| is associated with the saw 3| having a slot 52 through which the saw projects. The front portion of the saw plate 5| is pivotally mounted at 53, Figure '7, to a link 54 pivotally connected at 55 to the tool spindle housing II. To the rear portion of the saw plate is connected a spring 56 by a suitable pivotal connection 5! and the opposite end of the spring is looped around a pair of screws 58, Figure 9, or in any similar fashion secured rigidly to the housing The spring 56 normally urges the rear end portion 59 of the saw plate 5| radially outwardly of the saw so that when the power tool is released by the operator, as shown in Figure '7, the spring 56 will have sufficient pressure to push the end 59 down against the top of the work table or board surface 60 and automatically raise the housing H and saw 3| up away from the board 60 to prevent its marring or contacting the table while the motor I0 is still operating. When it is desired to saw, the operator merely presses down on the front portion of the power tool through the handle 38, as shown in Figure 6, and feeds the saw and plate along the board B to be cut. A suitable guard 6| is attached at 53 and 51 to the saw plate to protect the operator from the saw at all times.

Thus, in this sawing arrangement, there is provided a saw plate of yielding construction which automatically raises the saw from the work when the control handle 38 of the power tool is released. In this way, the operator may allow the motor ID to continuously operate so that it need not be shut olT each time a board or piece has been out and also allows the tool to be maintained in its tion, it is to be understood that the apparatus 1::

capable of mechanical alteration without departing from the spirit of the invention and that such mechanical arrangements and commercial adaptations as fall within the scope of the appended claims are intended to be included herein.

Having thus fully set forth and described this invention, what is claimed as new and desired to be secured by United States Letters Patent is:

1. In a portable power tool, a drive motor, a tool spindle member, a torque tube interconnecting said motor and tool spindle member, a power connection from said motor to drive cutting tools mounted on said member, an open end arm hook pivoted adjacent to said motor permitting entry of an arm between said hook and torque tube for carrying said power tool on the arm of the operator, and a control handle associated with said tool spindle member to facilitate the manipulation of said tool by the hand of the arm on which the tool is supported.

2. In a power tool, a drive motor, a tool spindle housing, a torque tube interconnecting said motor and housing, a tool spindle in said housing and means for driving said tool spindle from said motor, an open ended rigid arm hook connected to suspend said motor, torque tube, and housing in balanced condition below the operators arm, and a control means manipulatable by the operator's hand of said arm associated with said tool spindle housing for directing a cutting tool in said spindle to a work piece to be cut.

3. In a portable electric tool, an electric driving motor, a tool spindle housing, an elongated torque tube, a first tool spindle journaled in said housing, a drive shaft extending through said torque tube from said drive motor to drive said first tool spindle, a second tool spindle journaled in said housing substantially perpendicular to said first mentioned spindle, interchangeable tool support means on the outer end of said first tool spindle and on each end of said second mentioned tool spindle whereby a plurality of different types of cutting tools may be applied to any of said tool spindle mounting means, an open ended rigid arm hook associated with said torque tube and adjustable relative thereto in response to the particular work spindle put in operation to facilitate the manipulation of said tool while maintaining its balance under any operating condition and a control handle associated with said tool spindle housing to permit manipulation of said tool with one hand.

4. In a portable electrical tool, a driving motor, a tool spindle housing, an elongated torque tube, a tool spindle journaled in said housing in coaxial alignment with said torque tube, a drive shaft in said torque tube interconnecting power from said motor to said spindle, a second spindle mounted normal to said first mentioned spindle journaled in said housing and projecting each side thereof, interconnecting driving gearing from said first mentioned spindle to said second mentioned spindle, tool mounting means on each end of said second mentioned spindle and on the outer end of said first mentioned spindle, an open ended rigid arm hook hinged for swinging in a perpendicular plane to the axis of said torque tube and adjustable longitudinally on said tube to obtain a completely balanced suspension of said electric tool on the operators arm, and control handle means associated with said tool spindle housing to direct cutting tools mounted in said work spindles.

5. In a portable electrical tool, a driving motor, a tool spindle housing, an elongated torque tube, a tool spindle journaled in said housing in coaxial alignment with said torque tube, a drive shaft in said torque tube interconnecting power from said motor to said spindle, a second spindle mounted normal to said first mentioned spindle journaled in said housing and projecting each side thereof, interconnecting driving gearing from said first mentioned spindle to said second mentioned spindle, tool mounting means on each end of said second mentioned spindle and on the outer end of said first mentioned spindle, an open ended rigid arm hook hinged for swinging in a perpendicular plane to the axis of said torque tube and adjustable longitudinally on said tube to obtain a completely balanced suspension of said electric tool on the operators arm, control handle means associated with said tool spindle,

housing to direct cutting tools mounted in said tool spindles by the hand of the arm on which said tool is supported, and. means for swingably adjusting said handle in a plane perpendicular to the axis of said torque tube in accordance with the tool spindle selected to be used.

CHARLES RITTENHOUSE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 712,843 Paul Nov. 4, 1902 733,744 Raettig July 14, 1903 1,303,011 Aurand May 6, 1919 1,751,174 Richards et a1. Mar. 18, 1930 1,780,174 Crowe Nov. 4, 1930 2,301,264 Emery Nov. 10, 1942 FOREIGN PATENTS Number Country Date 403,973 Germany Oct. 9, 1924 785,882 France May 27, 1935 

